Discover: Is something in the water causing ALS, Alzheimer’s…? Good hypothesis (nothing more however)
Beta-Methylamino-L-alanine
Yesterday, about to catch a flight to SFO from Boston’s Logan airport after helping select next year’s Knight Fellows (and man it was hard not being able to take more), I grabbed some airplane reading: the May issue of Discover Magazine.
Lots of it was unvarnished pleasure, including one on Kepler’s new planets, and the cover story “You Are Not Human” which I’d have rephrased “You Are More than Human,” but fine reading.
More surprising and informative than any of those, yet also more problematic, is a piece by Kathleen McAuliffe, “There’s Something in the Water.” That link goes to a pdf on a page set up to make it awkward to read – and where the magazine keeps trying to steer readers to a place to pay to read it conveniently. Sorry about that – and nobody can blame the publisher for wanting a return on investment in this piece.
Perhaps you can find an easier to read version on line, or just pop over to the nearest newsstand and buy it.
What you’ll find is a thesis new to my recollection, perhaps not to a lot of people. It stems from epidemiology of Alzheimer’s disease, and somewhat to ALS and to related degenerative neurological diseases. They seem associated with proximity to bodies of water where blue-green algae bloom once in awhile. Best to call them cyanobacteria, as they are not true algae. A community of researchers suspects that an amino acid that these blooms secrete, beta-methylamino-L-alanine, or BMAA, is somehow bollixing neural circuits. One reads of a parallel to an ALS-like disease in Guam linked suggestively decades ago to fruit bats, and of bioconcentration of cyanobacterial BMAA in sea food, and much else that is interesting.
Here’s an irony. This story is of a genre I often regret for its rarity, and here I am grumbling at an example. Onward. We in science writing often say a frustration is the few opportunities to write about the process of science. News tends to stem from conclusions, the kind that tempt headline writers to slap “breakthrough” atop our carefully couched accounts.
But the tricky part about many process stories is that they are midstream snapshots of work that is incremental or uncertain in meaning. McCauliffe has such a piece of news. Legitimate enough, but unsure. That’s how it goes.
The piece’s troubling aspect is akin to mission creep in diplomacy and warfare. It starts off with suggestive evidence that BMAA is one cause of some dreadful ailments (It never implies it is the only or even major cause, by the way). But following the suggestive association, it declares we are dealing here with hypothesis, and a page later the story flat out labels it a theory. The epistemology of science is important. Science writers and their editors need to know and respect that theories have a good deal more heft and persuasive implication than hypotheses. Asserting a theory implies one has a hypothesis that has been subject to pass-fail tests in the collection of substantial evidence and that has passed. One may not have proof, but one supposedly has something pretty convincing. By the end of the piece one finds the pursuers of this hypothesis looking for “stronger proof,” implying they already have proof, and in need of the “clincher.” It has an anecdote of one patient whose life might have been saved had the BMAA hypothesis and related tests been available at the time. The tale thus has a trajectory with an implied certain splashdown point: MPAA is bad for the brain and cyanobacteria put it there.
The evidence in hand, and the coordinated search for more, are enough to sustain the story. This is enterprising reporting. It seems to advance the ball. It reveals vividly the process and emotional roller coaster of science as it proceeds. But I’d like it better had the tenor stuck with hypothesis. That means unproven, by a mile. There’s no buckle, much less a belt, to cinch or clinch.
I don’t find any other, recent mainline media accounts of the work. But I did find an oldish press release attesting to the validity of its line of inquiry.
Grist for the Mill:
University of Dundee Press Release (April 3, 2005);
Blogpost at Droplets – Bill Harding (Mar 18, 2011) CyanoAlert. This is from a South African environmental consultant with an alarming summation. It also is a good roundup of the general ground covered in the Discover article. It’s up to date. Says here that this line of research goes back 40 years.
A few days ago we posted on an article in the Boston Globe about inocculating larval zebra fish with cyanobacteria. Maybe the researchers should check the fish for Alzheimerish brain lesions? Just a thought.
Typo note: Original version of this post, in a failure of proofreading called gently to my attn. by reader Wendee Holtcamp, inexplicably substituted mpaa for bmaa about half way through. Oh, sigh.
- Charlie Petit
